Researchers from the Brien Holden Vision Institute have studied the weights of 549 human lenses across a diverse age range.

The study, which is published in Molecular Vision, supports the concept that there are two distinct phases to lens growth – one occurring during pre-natal development and the other during the post-natal phase.

Professor Bob Augusteyn, from the Brien Holden Vision Institute, said the study is the only research to his knowledge that measures lens weights over the whole life span.

Previously only about 20 weights had been measured for young lenses, he highlighted.

“This study, which measured both dry and wet lens weights, demonstrated that prenatally, the lens grows in a rapid logarithmic fashion, while postnatally, growth becomes linear and the chemistry of the new lens cells changes. Between birth and late teens, the lens changes shape from nearly round to elliptical,” Professor Augusteyn explained.

The research provides useful insight in the study of eye conditions such as cataracts and presbyopia.

The study revealed differences in the birth weight of lenses between males and females, with male lenses 4% heavier, suggesting that the pre-natal growth rate is higher.

After this point, male and female lens growth occurs at the same rate over the rest of the life course.

The weight difference at birth between males and females is also 4%, with the authors highlighting that this may mean the regulation of lens and body weight occurs through similar mechanisms.